diff options
| -rw-r--r-- | src/pkg/runtime/arch_arm.h | 2 | ||||
| -rw-r--r-- | src/pkg/runtime/asm_arm.s | 73 | ||||
| -rw-r--r-- | src/pkg/runtime/tls_arm.s | 7 |
3 files changed, 57 insertions, 25 deletions
diff --git a/src/pkg/runtime/arch_arm.h b/src/pkg/runtime/arch_arm.h index 3868d7862..637a334a0 100644 --- a/src/pkg/runtime/arch_arm.h +++ b/src/pkg/runtime/arch_arm.h @@ -6,7 +6,7 @@ enum { thechar = '5', BigEndian = 0, CacheLineSize = 32, - RuntimeGogoBytes = 84, + RuntimeGogoBytes = 60, #ifdef GOOS_nacl PhysPageSize = 65536, #else diff --git a/src/pkg/runtime/asm_arm.s b/src/pkg/runtime/asm_arm.s index 752ea08e5..3db907945 100644 --- a/src/pkg/runtime/asm_arm.s +++ b/src/pkg/runtime/asm_arm.s @@ -129,11 +129,19 @@ TEXT runtime·gosave(SB),NOSPLIT,$-4-4 // restore state from Gobuf; longjmp TEXT runtime·gogo(SB),NOSPLIT,$-4-4 MOVW 0(FP), R1 // gobuf - MOVW gobuf_g(R1), g - MOVW 0(g), R2 // make sure g != nil - MOVB runtime·iscgo(SB), R2 - CMP $0, R2 // if in Cgo, we have to save g - BL.NE runtime·save_g(SB) // this call will clobber R0 + MOVW gobuf_g(R1), R0 + BL setg<>(SB) + + // NOTE: We updated g above, and we are about to update SP. + // Until LR and PC are also updated, the g/SP/LR/PC quadruple + // are out of sync and must not be used as the basis of a traceback. + // Sigprof skips the traceback when SP is not within g's bounds, + // and when the PC is inside this function, runtime.gogo. + // Since we are about to update SP, until we complete runtime.gogo + // we must not leave this function. In particular, no calls + // after this point: it must be straight-line code until the + // final B instruction. + // See large comment in sigprof for more details. MOVW gobuf_sp(R1), SP // restore SP MOVW gobuf_lr(R1), LR MOVW gobuf_ret(R1), R0 @@ -143,8 +151,8 @@ TEXT runtime·gogo(SB),NOSPLIT,$-4-4 MOVW R11, gobuf_ret(R1) MOVW R11, gobuf_lr(R1) MOVW R11, gobuf_ctxt(R1) - CMP R11, R11 // set condition codes for == test, needed by stack split MOVW gobuf_pc(R1), R11 + CMP R11, R11 // set condition codes for == test, needed by stack split B (R11) // func mcall(fn func(*g)) @@ -162,7 +170,8 @@ TEXT runtime·mcall(SB),NOSPLIT,$-4-4 // Switch to m->g0 & its stack, call fn. MOVW g, R1 MOVW g_m(g), R8 - MOVW m_g0(R8), g + MOVW m_g0(R8), R0 + BL setg<>(SB) CMP g, R1 B.NE 2(PC) B runtime·badmcall(SB) @@ -218,7 +227,10 @@ oncurg: MOVW g, (g_sched+gobuf_g)(g) // switch to g0 - MOVW R2, g + MOVW R0, R5 + MOVW R2, R0 + BL setg<>(SB) + MOVW R5, R0 MOVW (g_sched+gobuf_sp)(R2), R3 // make it look like mstart called onM on g0, to stop traceback SUB $4, R3, R3 @@ -234,7 +246,8 @@ oncurg: // switch back to g MOVW g_m(g), R1 - MOVW m_curg(R1), g + MOVW m_curg(R1), R0 + BL setg<>(SB) MOVW (g_sched+gobuf_sp)(g), SP MOVW $0, R3 MOVW R3, (g_sched+gobuf_sp)(g) @@ -293,7 +306,8 @@ TEXT runtime·morestack(SB),NOSPLIT,$-4-0 MOVW g, (m_morebuf+gobuf_g)(R8) // Call newstack on m->g0's stack. - MOVW m_g0(R8), g + MOVW m_g0(R8), R0 + BL setg<>(SB) MOVW (g_sched+gobuf_sp)(g), SP BL runtime·newstack(SB) @@ -433,7 +447,8 @@ TEXT runtime·lessstack(SB),NOSPLIT,$-4-0 MOVW R0, m_cret(R8) // Call oldstack on m->g0's stack. - MOVW m_g0(R8), g + MOVW m_g0(R8), R0 + BL setg<>(SB) MOVW (g_sched+gobuf_sp)(g), SP BL runtime·oldstack(SB) @@ -485,7 +500,7 @@ TEXT runtime·asmcgocall_errno(SB),NOSPLIT,$0-12 TEXT asmcgocall<>(SB),NOSPLIT,$0-0 // fn in R1, arg in R0. MOVW R13, R2 - MOVW g, R5 + MOVW g, R4 // Figure out if we need to switch to m->g0 stack. // We get called to create new OS threads too, and those @@ -493,21 +508,27 @@ TEXT asmcgocall<>(SB),NOSPLIT,$0-0 MOVW g_m(g), R8 MOVW m_g0(R8), R3 CMP R3, g - BEQ 4(PC) + BEQ asmcgocall_g0 BL gosave<>(SB) - MOVW R3, g + MOVW R0, R5 + MOVW R3, R0 + BL setg<>(SB) + MOVW R5, R0 MOVW (g_sched+gobuf_sp)(g), R13 // Now on a scheduling stack (a pthread-created stack). +asmcgocall_g0: SUB $24, R13 BIC $0x7, R13 // alignment for gcc ABI - MOVW R5, 20(R13) // save old g + MOVW R4, 20(R13) // save old g MOVW R2, 16(R13) // save old SP - // R0 already contains the first argument BL (R1) // Restore registers, g, stack pointer. - MOVW 20(R13), g + MOVW R0, R5 + MOVW 20(R13), R0 + BL setg<>(SB) + MOVW R5, R0 MOVW 16(R13), R13 RET @@ -572,7 +593,8 @@ havem: // the earlier calls. // // In the new goroutine, -8(SP) and -4(SP) are unused. - MOVW m_curg(R8), g + MOVW m_curg(R8), R0 + BL setg<>(SB) MOVW (g_sched+gobuf_sp)(g), R4 // prepare stack as R4 MOVW (g_sched+gobuf_pc)(g), R5 MOVW R5, -12(R4) @@ -589,7 +611,8 @@ havem: // (Unlike m->curg, the g0 goroutine never uses sched.pc, // so we do not have to restore it.) MOVW g_m(g), R8 - MOVW m_g0(R8), g + MOVW m_g0(R8), R0 + BL setg<>(SB) MOVW (g_sched+gobuf_sp)(g), R13 MOVW savedsp-8(SP), R4 MOVW R4, (g_sched+gobuf_sp)(g) @@ -606,14 +629,20 @@ havem: RET // void setg(G*); set g. for use by needm. -TEXT runtime·setg(SB),NOSPLIT,$0-4 - MOVW gg+0(FP), g +TEXT runtime·setg(SB),NOSPLIT,$-4-4 + MOVW gg+0(FP), R0 + B setg<>(SB) + +TEXT setg<>(SB),NOSPLIT,$-4-0 + MOVW R0, g // Save g to thread-local storage. MOVB runtime·iscgo(SB), R0 CMP $0, R0 - BL.NE runtime·save_g(SB) + B.EQ 2(PC) + B runtime·save_g(SB) + MOVW g, R0 RET TEXT runtime·getcallerpc(SB),NOSPLIT,$-4-4 diff --git a/src/pkg/runtime/tls_arm.s b/src/pkg/runtime/tls_arm.s index 1b1cbc978..7a247ab19 100644 --- a/src/pkg/runtime/tls_arm.s +++ b/src/pkg/runtime/tls_arm.s @@ -22,12 +22,14 @@ // ARM code that will overwrite those registers. // NOTE: runtime.gogo assumes that R1 is preserved by this function. // runtime.mcall assumes this function only clobbers R0 and R11. -TEXT runtime·save_g(SB),NOSPLIT,$0 +// Returns with g in R0. +TEXT runtime·save_g(SB),NOSPLIT,$-4 #ifdef GOOS_nacl // nothing to do as nacl/arm does not use TLS at all. + MOVW g, R0 // preserve R0 across call to setg<> RET #endif - MRC 15, 0, R0, C13, C0, 3 // fetch TLS base pointer + MRC 15, 0, R0, C13, C0, 3 // fetch TLS base pointer // $runtime.tlsg(SB) is a special linker symbol. // It is the offset from the TLS base pointer to our // thread-local storage for g. @@ -38,6 +40,7 @@ TEXT runtime·save_g(SB),NOSPLIT,$0 #endif ADD R11, R0 MOVW g, 0(R0) + MOVW g, R0 // preserve R0 across call to setg<> RET // load_g loads the g register from pthread-provided |